Heterostructure device on the cleaved edge of a superlattice for terahertz power generation

A novel device structure for terahertz power generation is proposed. The energy-wave vector dispersion relation ε(k) of electrons in this structure can be designed such that it contains sections of a negative effective mass within favorable ranges of energy ε and wave vector k. This design is based on the parallel electron transport in the combination of a quantum wall and a superlattice. The quantum well is grown on the cleaved edge of this superlattice and provides channel 1 with a low effective electron mass. Electrons in the superlattice as channel 2 have a large effective mass in the lowest quantization miniband of the superlattice. The effective thickness of the channel 2 can be controlled with the electric field from the p-n junction that is formed between n-type sheet doping concentration in the barrier layer of the quantum well and the p-type doping concentration in the superlattice. A simplified calculation scheme for obtaining the hybrid electron dispersion relation for the quantum real space transfer in such a two-channel combination is described and illustrated